Engine fuel pump



Sept 3, 1929- E. voN sALls 11,726,937

' ENGINE FUEL umP Filed Dec. 12, 1925 I il [E *-f V l Wa. l f l v j l v@Q fm QNVEEQTOR Patented se. 3, 1929.

UNITED STATES A 1,126,937 PATENTy oE-EICE.

RDUARD von sALIs, or WINTERTHUR, SWITZERLAND, AssIGNoR To 'BUSCH-suman:mos-DIESEL ENGINE COMPANY, orsT. LOUIS, MISSOURI, A CORPORATION or'MISSOURI.

ENGINE FUEL PUMP.

A\pp1ication filed December 12, 1925, Serial No. 75,004, and inSwitzerland January l0, 1925.

l The object of the invention is to simplify the operation andconstruction of the .fuel 1njecting.' means of oil `engines,partlcularly those in which the oil fuel is injected solid' or withoutthe aid of high pressure injection air, but without limitation to thisor any class of engine. More particularly the invention is animprovement in fuel injection systems of the kind in which so-calledaccumulators Vare employed for putting the fuel under pres.

Fig. 2 is a circle diagram illustrating thesequence of action.

The pump chamber is provided with a suc# tion or intake valve 1 and adischarge valve 3 which opens to the spray nozzle or injec tion device 4of the internal combustion engine. The two valves seat outwardly7 andare normally closed by a spring although any other style and arrangementof the pump valves could be employed.

The pump plunger 5 is reciprocated by the 35. crank or eccentric 6 on asuitable enginedriven lay shaft as usual and the connection between suchshaft and the plunger is constituted by a cross-head structure, in whichthe accumulator device is carried or with which it is associated so asto produce the effect here# inafter described;

In the form shown the accumulator consists 'controlled by the durationof thevopen period of the suction valve. This valve is opened by thebell crank lever 10 and its spring 11. One end of this crank extendsinto the path of the plunger crosshead and is arranged so that the valveis open during all the suction stroke and for a part of the compressingstroke, or

p until the crosshead strikes'the bell crank at some point -in itscompressing stroke and a1- lows it to seat. When the suction valve'isthus permitted to seat the advance' of the plunger stops, theaccumulator spring is compressed by the rcontinuing movement of thecrosshead and the fuel remaining in the ypump isV put under acorresponding pressure.

At the proper time, say at or about conipression dead center of theengine, the discharge valve 3 is opened bythe cam 12 acting on itthrough the valve lever 13 and a portion of the fuel then undercompression in the pump is thereupon delivered to the linjection nozzle4 under high velocity. The quantity thus delivered is greater or lessaccording as the suction valve was closed earlier or laterl in thepumping stroke. The time of such closing is subject to variation as byshifting the fulcrum of the suction valve bell crank thus causingearlier or later engagement of the latter by the crosshead. This may bedone by hand or it may be done by theen ine governor, as indicated inthe drawing. n bviously the details of the leverage Zabove described,whereby the crosshead or pump shaft causes the closing of the suctionvalve and whereby the discharge valve is 9"() a opened, are subject tomodification to any extent according to circumstances and the preferenceof the maker. The fuel delivery cam 12 will be understood to be drivenby the engine, although the driving connection is not shown. Thedischarge valve is not influenced by the control exerted by thegovernor, and

may, if preferred, be located directly on the l engine cylinder head andclose to the combustion lspace so as to constitute the engine injectorvalve as well as the pump discharge` valve.

In the usual injection system, employing' an accumulator spring in whichenergy v1s stored during the compressionstroke of the pump and theinjection takes place on the release of the s ring, the discharge orinjection valve must e subject to governor control, i. e. its openingmust conform to the load vand 2 0 the discharge or Injector valve,

25 ternal combustion engines,

speed of the engine. In such case, if the en-V gine is reversed indirection, the parts which are controlled by the governor must .also bereversed. This is not necessary with the 5' present invention by reasonof the association of ,the accumulator spring with theY plunger'operating mechanism' and as indicated by the dotted line, the camnoseof the fuel discharge. cam 12 is of symmetrical form so that toreverse the engine it is suiiicient to reverse mere- I -ly the startingmechanism.

In the diagram of Fig. 2, the upper arc 14-15 represents the suctionstroke; 15-'-16 .the compressing stroke during which excess l5 fuel isreturned through the suction valve;

point 16 which is variable, representsthe time of closing of the suctionvalve; arc 16-17 represents the continuing stroke of the crosshead, andpoint 1'? represents the opening of and accumulatorl comprisinga'plunger barrel,`a plunger,

14 being its.

specification. a suction valve, and a delivery l valve, in combinationwith engine#operated 4reciprocating. means to effect through' positivemeans the suction stroke of the plunger, and to effect through resilientmeans the de# livery stroke of the plunger, suction valve lifting meansoperated by said reciprocating means, control means to vary the point ofplunger travel at which said lifting means allows the suction valve toclose, and engineoperated means to open said delivery valve.

2. In an airless fuel injection-device for internal combustion engines,a combined pump and accumulator comprising a plunger barrel, a plunger,a suction valve, and a delivery valve, both said valves closingoutwardly, in combination with engine-operated reciprocating means toeffect through positive means the suction' stroke of the plunger, and toeffeet through resilient means the delivery stroke of the lunger,suction valve lifting means operatedJ by said reciprocating means,control means to va the point of plunger travel a't which said liftingmeans allows the suction-valve to close, and engine-operated means toopen said delivery valve. v

In testimony whereof, I have signed this EDUABD von Sams.

